BACKGROUND: Acute appendicitis (AA) is the most common surgical disease, and appendectomy is the treatment of choice in the majority of cases. A correct diagnosis is key for decreasing the negative appendectomy rate. The management can become difficult in case of complicated appendicitis. The aim of this study is to describe the worldwide clinical and diagnostic work-up and management of AA in surgical departments. METHODS: This prospective multicenter observational study was performed in 116 worldwide surgical departments from 44 countries over a 6-month period (April 1, 2016-September 30, 2016). All consecutive patients admitted to surgical departments with a clinical diagnosis of AA were included in the study. RESULTS: A total of 4282 patients were enrolled in the POSAW study, 1928 (45%) women and 2354 (55%) men, with a median age of 29 years. Nine hundred and seven (21.2%) patients underwent an abdominal CT scan, 1856 (43.3%) patients an US, and 285 (6.7%) patients both CT scan and US. A total of 4097 (95.7%) patients underwent surgery; 1809 (42.2%) underwent open appendectomy and 2215 (51.7%) had laparoscopic appendectomy. One hundred eighty-five (4.3%) patients were managed conservatively. Major complications occurred in 199 patients (4.6%). The overall mortality rate was 0.28%. CONCLUSIONS: The results of the present study confirm the clinical value of imaging techniques and prognostic scores. Appendectomy remains the most effective treatment of acute appendicitis. Mortality rate is low.

1183rd Department of Surgery IASO General Hospital Athens Greece

1231st Department of Surgery Department of Abdominal Thoracic Surgery and Traumatology General University Hospital Prague Czech Republic

1st Department of Surgery Kavala General Hospital Kavala Greece

1st Department of Surgery Tzaneio Piraeus Greece

1st Surgical Clinic St Spiridon University Hospital Iasi Romania

2nd Department of Surgery Aretaieion University Hospital National and Kapodistrian University of Athens Athens Greece

554th Surgical Department Aristotle University of Thessaloniki Thessaloniki Greece

643rd Department of General Surgery Jagiellonian University Medical College Krakow Poland

762nd Department of Surgery Jagiellonian University Medical College Krakow Poland

863rd Department of Surgery Ahepa University Hospital Thessaloniki Greece

873rd Department of Surgery Attikon University Hospital National and Kapodistrian University of Athens Medical School Athens Greece

Abdominal surgery UMC Ljubljana Ljubljana Slovenia

Acute Care Surgery LAC USC Medical Center California USA

Acute Care Surgery North Estonia Medical Center Tallinn Estonia

Chirurgia Città di Castello Hospital Città di Castello Italy

Chirurgie Chud Borgou Alibori Parakou Benin

Cirugía General y del Aparato Digestivo Hospital Universitario Miguel Servet Zaragoza Spain

Cirurgia do Trauma Hospital Escola Padre Albino Catanduva Brazil

Clinic for Emergency Surgery Faculty of Medicine University of Belgrade Belgrade Serbia

Clinic of surgery Department of Gastrointestinal Surgery University Hospital Centre Zagreb Zagreb Croatia

Colorectal Surgery Clinic for Surgery University Clinical Center Tuzla Tuzla Bosnia and Herzegovina

DEA La Sapienza Università di Roma Policlinico Umberto 1 Rome Italy

Department of Abdominal Surgery Vladimir City Clinical Hospital of Emergency Medicine Vladimir Russia

Department of Biomedical Sciences and Public Health Unit of Hygiene Preventive Medicine and Public Health UNIVPM Ancona Italy

Department of Clinical and Experimental Sciences University of Brescia Brescia Italy

Department of Emergency Surgery and Trauma Centre University Hospital Kraków Poland

Department of Endoscopic Metabolic and Soft Tissue Tumors Surgery The University Hospital in Krakow Kraków Poland

Department of Gastrointestinal Surgery Insular University Hospital of Gran Canaria Las Palmas Spain

Department of General and Digestive Surgery Hospital Universitario Doctor Peset Valencia Spain

Department of General and Thoracic Surgery University Hospital Giessen Germany

Department of General Oncological Metabolic and Thoracic Surgery Military Institute of Medicine in Warsaw Warsaw Poland

Department of General Surgery and Emergency Medicine University Hospital Kraków Poland

Department of General Surgery Karadeniz Technical University Farabi Hospital Trabzon Turkey

Department of General Surgery Kocaeli University Kocaeli Turkey

Department of General Surgery Medical University of Plovdiv UMHAT Eurohospital Plovdiv Bulgaria

Department of General Surgery Post Graduate Institute of Medical Sciences Rohtak India

Department of General Surgery Sant'Antonio Abate Hospital Gallarate Italy

Department of General Surgery Trauma and Emergency Surgery Division ABC Medical School Santo Andreì SP Brazil

Department of Surgery 2nd Surgical Clinic Emergency Hospital of Craiova Craiova Romania

Department of Surgery Bufalini Hospital Cesena Italy

Department of Surgery Edendale Hospital Pietermaritzburg South Africa

Department of Surgery Harbor UCLA Medical Center Torrance USA

Department of Surgery Hospital of Lithuanian University of Health Sciences Kaunas Clinics Kaunas Lithuania

Department of Surgery Inje University Ilsan Paik Hospital Goyang Republic of Korea

Department of Surgery Macerata Hospital Macerata Italy

Department of Surgery Medical School University of Pécs Pécs Hungary

Department of Surgery Radiology Anaesthetics and Intensive Care University of the West Indies Kingston Jamaica

Department of Surgery Tianjin Nankai Hospital Tianjin China

Department of Visceral Digestive and Oncologic Surgery Clinique Sainte Marie Cambrai France

Digestive and Endocrinal Surgery University Hospital Angers France

Digestive Surgery CHU Amiens Picardie Amiens France

Division of Digestive Surgery and Urology Turku University Hospital Turku Finland

Division of Trauma and Acute Care Surgery Department of Surgery Fundación Valle del Lili and Universidad del Valle Cali Colombia

Division of Trauma Surgery Hospital de Clinicas University of Campinas Campinas Brazil

Emergency Surgery Azienda Ospedaliera Universitaria Policlinico Paolo Giaccone Palermo Italy

Emergency surgery City Hospital Mozyr Belarus

Emergency Surgery Maggiore Hospital Bologna Italy

Emergency Surgery Mansoura University Hospital Mansoura Egypt

Emergency Surgery S Anna Teaching Hospital Ferrara Italy

Emergency Surgery Unit Maggiore University Hospital Parma Italy

Faculty of Medicine Department of Surgery Siriraj Hospital Mahidol University Bangkok Thailand

General and Digestive Surgery Hospital Fundación Jimenez Diaz Madrid Spain

General and Emergency Surgery Riga East University Hospital Gailezers Riga Latvia

General and Emergency Surgery San Giovanni Bosco Hospital Turin Italy

General Emergency Surgery Infermi Hospital Rimini Italy

General Hospital George Papanikoalou Thessaloniki Greece

General Surgery and Polytrauma San Carlo Borromeo Hospital Milan Italy

General Surgery and Polytrauma University Hospital Medical College Jagiellonian University Kraków Poland

General Surgery Bahrain Defence Force Hospital Manama Bahrain

General Surgery Baskent Universitesi Adana Eğitim ve Uygulama Hastanesi Adana Turkey

General Surgery Centro Hospitalar São João Porto Portugal

General Surgery City Hospital 1 Moscow Russia

General Surgery Clinical Hospital at Chelyabinsk Station OJSC Russian Railways Chelyabinsk Russian Federation

General Surgery Colorectal Unit Hospital de Braga Braga Portugal

General Surgery Department Mansoura Faculty of Medicine Mansoura University Mansoura Egypt

General Surgery Elazig Training and Research Hospital Elazig Turkey

General Surgery Emergency Hospital of Bucharest Bucharest Romania

General Surgery Erzincan University Mengucek Gazi Training and Research Hospital Erzincan Turkey

General Surgery Hadassah Medical Center Jerusalem Israel

General Surgery Hospital Civil de Guadalajara Dr Juan 1 Menchaca Guadalajara Mexico

General Surgery Hospital Garcia de Orta Lisbon Portugal

General Surgery Hospital General Regional 1 1 M S S Cuernavaca Mexico

General Surgery Hospital Habib Bouguefa de Bizerte Bizerte Tunisia

General Surgery Hospital Municipal Dr Jose de Carvalho Florence Sao Jose Dos Campos Brazil

General Surgery Jubilee Mission Medical College and Research Institute Thrissur India

General Surgery K R Hospital Mysore India

General Surgery Khartoum Teaching Hospital Khartoum Sudan

General Surgery King Abdullah University Hospital Irbid Jordan

General Surgery King George's Medical University Lucknow India

General Surgery Kuala Krai Hospital Kuala Krai Kelantan Malaysia

General Surgery Lewisham and Greenwich NHS Trust London UK

General Surgery Numune Training and Research Hospital Adana Turkey

General Surgery Russells Hall Hospital Birmingham UK

General Surgery S S Annunziata Hospital Taranto Italy

General Surgery Sakarya University School of Medicine Sakarya Turkey

General Surgery Samsun Training and Research Hospital Samsun Turkey

General Surgery Scarborough York Teaching Hospital Scarborough UK

General Surgery Tan Tock Seng Hospital Singapore Singapore

General Surgery Training and Research Hospital of Mustafa Kemal University Hatay Turkey

General Surgery Trauma University Hospital Tirana Albania

General Surgery University Hospital St George Plovdiv Bulgaria

General Surgery University Hospitals Birmingham NHS Foundation Trust Birmingham UK

Laparoscopic and Metabolic Surgery KIMS Hospital Cochin India

Primary Care Primary Health Care Centre of Kissamos Chania Greece

Surgery 1st University Clinic Tbilisi Georgia

Surgery Ahmadu Bello University Teaching Hospital Zaria Zaria Nigeria

Surgery and Anatomy Clinics Hospital Ribeirão Preto Brazil

Surgery and Obstetrics Gynaecology Regional Hospital Limbe Cameroon

Surgery ASTS Spedali Civili Brescia Montichiari Italy

Surgery Bharati Vidyapeeth Deemed University Medical College and Hospital Sangli Maharashtra India

Surgery CHVNG E EPE Vila Nova de Gaia Portugal

Surgery Departement Medical School of Fezm Sidi Mohamed Benabdellah University Fez Morocco

Surgery Department 2 Tbilisi State Medical University Tbilisi Georgia

Surgery Government Medical College and Hospital Chandigarh India

Surgery Hamad General Hospital Doha Qatar

Surgery Hospital and Oncological Centre Novy Jicin Novy Jicin Czech Republic

Surgery Hospital San Juan de Dios de La Serena La Serena Chile

Surgery Kipshidze Central University Hospital Tbilisi Georgia

Surgery Kwara State General Hospital Ilorin Kwara Nigeria

Surgery S M S Medical college Jaipur India

Surgery Therezinha de Jesus University Hospital Juiz de Fora Brazil

Surgery University Hospital Greifswald Germany

Surgery University of Ilorin Teaching Hospital Ilorin Nigeria

Surgical Department Agios Savvas Anticaner Hospital Athens Greece

Surgical Department General Hospital of Larissa Larissa Greece

Surgical Department Konstantopouleio General Hospital Athens Greece

Surgical Department Landesklinikum Hainburg Hainburg An Der Donau Austria

Surgical Disciplines Regional Clinical Hospital Kaliningrad Russia

Trauma Acute Care Surgery University of California San Diego San Diego USA

Trauma and Emergency Surgery Chang Gung Memorial Hospital Taoyuan Taiwan

University Hospital of the West Indies Kingston Jamaica

Upper GI General Surgery University Hospitals Birmingham NHS Foundation Trust Birmingham UK

Zobrazit více v PubMed

Addiss DG, Shaffer N, Fowler BS, Tauxe RV. The epidemiology of appendicitis and appendectomy in the United States. Am J Epidemiol. 1990;132:910–925. doi: 10.1093/oxfordjournals.aje.a115734. PubMed DOI

Blomqvist P, Ljung H, Nyren O, Ekbom A. Appendectomy in Sweden 1989–1993 assessed by the Inpatient Registry. J ClinEpidemiol. 1998;51:859–865. PubMed

Margenthaler JA, Longo WE, Virgo KS, Johnson FE, Oprian CA, Henderson WG, et al. Risk factors for adverse outcomes after the surgical treatment of appendicitis in adults. Ann Surg. 2003;238:59–66. PubMed PMC

Alvarado A. A practical score for the early diagnosis of acute appendicitis. Ann Emerg Med. 1986;15:557–564. doi: 10.1016/S0196-0644(86)80993-3. PubMed DOI

Andersson M, Andersson RE. The appendicitis inflammatory response score: a tool for the diagnosis of acute appendicitis that outperforms the Alvarado score. World J Surg. 2008;32:1843–1849. doi: 10.1007/s00268-008-9649-y. PubMed DOI

Hansson J, Korner U, Khorram-Manesh A, Solberg A, Lundholm K. Randomized clinical trial of antibiotic therapy versus appendicectomy as primary treatment of acute appendicitis in unselected patients. Br J Surg. 2009;96:473–481. doi: 10.1002/bjs.6482. PubMed DOI

Styrud J, Eriksson S, Nilsson I, Ahlberg G, Haapaniemi S, Neovius G, et al. Appendectomy versus antibiotic treatment in acute appendicitis. A prospective multicenter randomized controlled trial. World J Surg. 2006;30:1033–1037. doi: 10.1007/s00268-005-0304-6. PubMed DOI

Vonns C, Barry C, Maitre S, Pautrat K, Leconte M, Costaglioli B, et al. Amoxicillin plus clavulanic acid versus appendicectomy for treatment of acute uncomplicated appendicitis: an open-label, non-inferiority, randomised controlled trial. Lancet. 2011;377:1573–1579. doi: 10.1016/S0140-6736(11)60410-8. PubMed DOI

Salminen P, Paajanen H, Rautio T, Nordstrom P, Aarnio M, Rantanen T, et al. Antibiotic therapy vs appendectomy for treatment of uncomplicated acute appendicitis: the APPAC Randomized Clinical Trial. JAMA. 2015;313:2340–2348. doi: 10.1001/jama.2015.6154. PubMed DOI

Ansaloni L, Catena F, Coccolini F, Ercolani G, Gazzotti F, Pasqualini E, et al. Surgery versus conservative antibiotic treatment in acute appendicitis: a systematic review and meta-analysis of randomized controlled trials. Dig Surg. 2011;28:210–221. doi: 10.1159/000324595. PubMed DOI

Liu K, Fogg L. Use of antibiotics alone for treatment of uncomplicated acute appendicitis: a systematic review and meta-analysis. Surgery. 2011;150:673–683. doi: 10.1016/j.surg.2011.08.018. PubMed DOI

Wilms IM, de Hoog DE, de Visser DC, Janzing HM. Appendectomy versus antibiotic treatment for acute appendicitis. Cochrane Database Syst Rev. 2011;11:CD008359. PubMed

Varadhan KK, Neal KR, Lobo DN. Safety and efficacy of antibiotics compared with appendicectomy for treatment of uncomplicated acute appendicitis: meta-analysis of randomised controlled trials. BMJ. 2012;344:e2156. doi: 10.1136/bmj.e2156. PubMed DOI PMC

Di Saverio S, Sibilio A, Giorgini E, Biscardi A, Villani S, Coccolini F, et al. The NOTA Study (Non Operative Treatment for Acute Appendicitis): prospective study on the efficacy and safety of antibiotics (amoxicillin and clavulanic acid) for treating patients with right lower quadrant abdominal pain and long-term follow-up of conservatively treated suspected appendicitis. Ann Surg. 2014;260:109–117. doi: 10.1097/SLA.0000000000000560. PubMed DOI

Apisarnthanarak P, Suvannarerg V, Pattaranutaporn P, Charoensak A, Raman SS, Apisarnthanarak A. Alvarado score: can it reduce unnecessary CT scans for evaluation of acute appendicitis? Am J Emerg Med. 2015;33:266–270. doi: 10.1016/j.ajem.2014.11.056. PubMed DOI

Nelson DW, Causey MW, Porta CR, McVay DP, Carnes AM, Johnson EK, et al. Examining the relevance of the physician's clinical assessment and the reliance on computed tomography in diagnosing acute appendicitis. Am J Surg. 2013;205:452–456. doi: 10.1016/j.amjsurg.2012.07.038. PubMed DOI

Duda JB, Lynch ML, Bhatt S, Dogra VS. Computed tomography mimics of acute appendicitis: predictors of appendiceal disease confirmed at pathology. J Clin Imaging Sci. 2012;2:73. doi: 10.4103/2156-7514.104306. PubMed DOI PMC

Horton MD, Counter SF, Florence MG, Hart MJ. A prospective trial of computed tomography and ultrasonography for diagnosing appendicitis in the atypical patient. Am J Surg. 2000;179:379–381. doi: 10.1016/S0002-9610(00)00372-X. PubMed DOI

Pinto Leite N, Pereira JM, Cunha R, Pinto P, Sirlin C. CT evaluation of appendicitis and its complications: imaging techniques and key diagnostic findings. AJR Am J Roentgenol. 2005;185:406–417. doi: 10.2214/ajr.185.2.01850406. PubMed DOI

Bennet J, Boddy A, Rhodes M. Choice of approach for appendicectomy: a meta-analysis of open versus laparoscopic appendicectomy. Surg Laparosc Endosc Percutan Tech. 2007;17:245–255. doi: 10.1097/SLE.0b013e318058a117. PubMed DOI

Liu Z, Zhang P, Ma Y, Chen H, Zhou Y, Zhang M, et al. Laparoscopy or not: a meta-analysis of the surgical effects of laparoscopic versus open appendicectomy. Surg Laparosc Endosc Percutan Tech. 2010;20:362–370. doi: 10.1097/SLE.0b013e3182006f40. PubMed DOI

Sauerland S, Jaschinski T, Neugebauer EA. Laparoscopic versus open surgery for suspected appendicitis. Cochrane Database Syst Rev. 2010;10:CD001546. PubMed

Wei B, Qi CL, Chen TF, Zheng ZH, Huang JL, Hu BG, Wei HB. Laparoscopic versus open appendectomy for acute appendicitis: a metaanalysis. Surg Endosc. 2011;25:1199–1208. doi: 10.1007/s00464-010-1344-z. PubMed DOI

Ohtani H, Tamamori Y, Arimoto Y, Nishiguchi Y, Maeda K, Hirakawa K. Meta-analysis of the results of randomized controlled trials that compared laparoscopic and open surgery for acute appendicitis. J Gastrointest Surg. 2012;16:1929–1939. doi: 10.1007/s11605-012-1972-9. PubMed DOI

Woodham BL, Cox MR, Eslick GD. Evidence to support the use of laparoscopic over open appendicectomy for obese individuals: a meta-analysis. Surg Endosc. 2012;26:2566–2570. doi: 10.1007/s00464-012-2233-4. PubMed DOI

Bradley EL, 3rd, Isaacs J. Appendiceal abscess revisited. Arch Surg. 1978;113:130–132. doi: 10.1001/archsurg.1978.01370140020003. PubMed DOI

Bagi P, Dueholm S. Nonoperative management of the ultrasonically evaluated appendiceal mass. Surgery. 1987;101:602–605. PubMed

Oliak D, Yamini D, Udani VM, Lewis RJ, Arnell T, Vargas H, et al. Initial nonoperative management for periappendiceal abscess. Dis Colon Rectum. 2001;44:936–941. doi: 10.1007/BF02235479. PubMed DOI

Solomkin JS, Mazuski JE, Bradley JS, Rodvold KA, Goldstein EJ, Baron EJ, et al. Diagnosis and management of complicated intra-abdominal infection in adults and children: guidelines by the Surgical Infection Society and the Infectious Diseases Society of America. Clin Infect Dis. 2010;50:133–164. doi: 10.1086/649554. PubMed DOI

Brown CV, Abrishami M, Muller M, Velmahos GC. Appendiceal abscess: immediate operation or percutaneous drainage? Am Surg. 2003;69:829–832. PubMed

Sartelli M, Viale P, Koike K, Pea F, Tumietto F, van Goor H, et al. WSES consensus conference: guidelines for first-line management of intra-abdominal infections. World J Emerg Surg. 2011;6:2. doi: 10.1186/1749-7922-6-2. PubMed DOI PMC

Corfield L. Interval appendicectomy after appendiceal mass or abscess in adults: what is “best practice”? Surg Today. 2007;37:1–4. doi: 10.1007/s00595-006-3334-2. PubMed DOI

Roach JP, Partrick DA, Bruny JL, Allshouse MJ, Karrer FM, Ziegler MM. Complicated appendicitis in children: a clear role for drainage and delayed appendectomy. Am J Surg. 2007;194:769–772. doi: 10.1016/j.amjsurg.2007.08.021. PubMed DOI

You KS, Kim DH, Yun HY, Jang LC, Choi JW, Song YJ, et al. The value of a laparoscopic interval appendectomy for treatment of a periappendiceal abscess: experience of a single medical center. Surg Laparosc Endosc Percutan Tech. 2012;22:127–130. doi: 10.1097/SLE.0b013e318244ea16. PubMed DOI

Keckler SJ, Tsao K, Sharp SW, Ostlie DJ, Holcomb GW, III, St Peter SD. Resource utilization and outcomes from percutaneous drainage and interval appendectomy for perforated appendicitis with abscess. J Pediatr Surg. 2008;43:977–980. doi: 10.1016/j.jpedsurg.2008.02.019. PubMed DOI PMC

Lasson A, Lundagårds J, Lorén I, Nilsson PE. Appendiceal abscesses: primary percutaneous drainage and selective interval appendicectomy. Eur J Surg. 2002;168:264–269. doi: 10.1002/ejs.44. PubMed DOI

Kaminski A, Liu IL, Applebaum H, Lee SL, Haigh PI. Routine interval appendectomy is not justified after initial nonoperative treatment of acute appendicitis. Arch Surg. 2005;140:897–901. doi: 10.1001/archsurg.140.9.897. PubMed DOI

Gomes CA, Sartelli M, Di Saverio S, Ansaloni L, Catena F, Coccolini F, et al. Acute appendicitis: proposal of a new comprehensive grading system based on clinical, imaging and laparoscopic findings. World J Emerg Surg. 2015;10:60. doi: 10.1186/s13017-015-0053-2. PubMed DOI PMC

Charlson ME, Pompei P, Ales KL, MacKenzie CR. A new method of classifying prognostic comorbidity in longitudinal studies: development and validation. J Chronic Dis. 1987;40:373–383. doi: 10.1016/0021-9681(87)90171-8. PubMed DOI

Dindo D, Demartines N, Clavien PA. Classification of surgical complications: a new proposal with evaluation in a cohort of 6336 patients and results of a survey. Ann Surg. 2004;240:205–213. doi: 10.1097/01.sla.0000133083.54934.ae. PubMed DOI PMC

Ambe PC, Orth V, Gödde D, Zirngibl H. Improving the preoperative diagnostic accuracy of acute appendicitis. Can fecal calprotectin be helpful. PLoS One. 2016;11:e0168769. doi: 10.1371/journal.pone.0168769. PubMed DOI PMC

Gorter RR, Eker HH, Gorter-Stam MA, Abis GS, Acharya A, Ankersmit M, et al. Diagnosis and management of acute appendicitis. EAES consensus development conference 2015. Surg Endosc. 2016;30:4668–4690. doi: 10.1007/s00464-016-5245-7. PubMed DOI PMC

Shogilev DJ, Duus N, Odom SR, Shapiro NI. Diagnosing appendicitis: evidence-based review of the diagnostic approach in 2014. West J Emerg Med. 2014;15:859–871. doi: 10.5811/westjem.2014.9.21568. PubMed DOI PMC

Pickhardt PJ, Lawrence EM, Pooler BD, Bruce RJ. Diagnostic performance of multidetector computed tomography for suspected acute appendicitis. Ann Intern Med. 2011;154:789–796. doi: 10.7326/0003-4819-154-12-201106210-00006. PubMed DOI

Krajewski S, Brown J, Phang PT, Raval M, Brown CJ. Impact of computed tomography of the abdomen on clinical outcomes in patients with acute right lower quadrant pain: a meta-analysis. Can J Surg. 2011;54:43–53. doi: 10.1503/cjs.023509. PubMed DOI PMC

Di Saverio S, Birindelli A, Kelly MD, Catena F, Weber DG, Sartelli M, et al. WSES Jerusalem guidelines for diagnosis and treatment of acute appendicitis. World J Emerg Surg. 2016;11:34. doi: 10.1186/s13017-016-0090-5. PubMed DOI PMC

Gomes CA, Nunes TA, Fonseca Chebli JM, Junior CS, Gomes CC. Laparoscopy grading system of acute appendicitis: new insight for future trials. Surg Laparosc Endosc Percutan Tech. 2012;22:463–466. doi: 10.1097/SLE.0b013e318262edf1. PubMed DOI

Rollins KE, Varadhan KK, Neal KR, Lobo DN. Antibiotics versus appendicectomy for the treatment of uncomplicated acute appendicitis: an updated meta-analysis of randomised controlled trials. World J Surg. 2016;40:2305–2318. doi: 10.1007/s00268-016-3561-7. PubMed DOI

Podda M, Cillara N, Di Saverio S, Lai A, Feroci F, Luridiana G, et al. Antibiotics-first strategy for uncomplicated acute appendicitis in adults is associated with increased rates of peritonitis at surgery. A systematic review with meta-analysis of randomized controlled trials comparing appendectomy and non-operative management with antibiotics. Surgeon. 2017;15:303–314. doi: 10.1016/j.surge.2017.02.001. PubMed DOI

Jaschinski T, Mosch C, Eikermann M, Neugebauer EA. Laparoscopic versus open appendectomy in patients with suspected appendicitis: a systematic review of meta-analyses of randomised controlled trials. BMC Gastroenterol. 2015;15:48. doi: 10.1186/s12876-015-0277-3. PubMed DOI PMC

Massoomi H, Mills S, Dolich MO, Ketana N, Carmichael JC, Nguyen NT, et al. Comparison of outcomes of laparoscopic versus open appendectomy in adults: data from the nationwide inpatient sample (NIS), 2006–2008. J Gastrointest Surg. 2011;15:2226–2231. doi: 10.1007/s11605-011-1613-8. PubMed DOI

Xiao Y, Shi G, Zhang J, Cao JG, Liu LJ, Chen TH, et al. Surgical site infection after laparoscopic and open appendectomy: a multicenter large consecutive cohort study. Surg Endosc. 2014;29:1384–1393. doi: 10.1007/s00464-014-3809-y. PubMed DOI

Wilson DG, Bond AK, Ladwa N, Sajid MS, Baig MK, Sains P. Intra-abdominal collections following laparoscopic versus open appendicectomy: an experience of 516 consecutive cases at a district general hospital. Surg Endosc. 2013;27:2351–2356. doi: 10.1007/s00464-012-2778-2. PubMed DOI

Swank HA, Eshuis EJ, van Berge Henegouwen MI, Bemelman WA. Short- and long-term results of open versus laparoscopic appendectomy. World J Surg. 2011;35:1221–1226. doi: 10.1007/s00268-011-1088-5. PubMed DOI PMC

Li X, Zhang J, Sang L, Zhang W, Chu Z, Li X, et al. Laparoscopic versus conventional appendectomy—a meta-analysis of randomized controlled trials. BMC Gastroenterol. 2010;10:129. doi: 10.1186/1471-230X-10-129. PubMed DOI PMC

Emil S, Elkady S, Shbat L, Youssef F, Baird R, Laberge JM, et al. Determinants of postoperative abscess occurrence and percutaneous drainage in children with perforated appendicitis. Pediatr Surg Int. 2014;30:1265–1271. doi: 10.1007/s00383-014-3617-4. PubMed DOI

Isaksson K, Montgomery A, Moberg AC, Andersson R, Tingstedt B. Long-term follow-up for adhesive small bowel obstruction after open versus laparoscopic surgery for suspected appendicitis. Ann Surg. 2014;259:1173–1177. doi: 10.1097/SLA.0000000000000322. PubMed DOI

Gandaglia G, Ghani KR, Sood A, Meyers JR, Sammon JD, Schmid M, et al. Effect of minimally invasive surgery on the risk for surgical site infections: results from the National Surgical Quality Improvement Program (NSQIP) Database. JAMA Surg. 2014;149:1039–1044. doi: 10.1001/jamasurg.2014.292. PubMed DOI

Advani V, Ahad S, Gonczy C, Markwell S, Hassan I. Does resident involvement effect surgical times and complication rates during laparoscopic appendectomy for uncomplicated appendicitis? An analysis of 16,849 cases from the ACS-NSQIP. Am J Surg. 2012;203:347–351. doi: 10.1016/j.amjsurg.2011.08.015. PubMed DOI

Kanona H, Al Samaraee A, Nice C, Bhattacharya V. Stump appendicitis: a review. Int J Surg. 2012;10:425–428. doi: 10.1016/j.ijsu.2012.07.007. PubMed DOI

Bucher P, Mathe Z, Demirag A, Morel P. Appendix tumors in the era of laparoscopic appendectomy. Surg Endosc. 2004;18:1063–1066. doi: 10.1007/s00464-003-9255-x. PubMed DOI

Ma KW, Chia NH, Yeung HW, Cheung MT. If not appendicitis, then what else can it be? A retrospective review of 1492 appendectomies. Hong Kong Med J. 2010;16:12–17. PubMed

Ceresoli M, Zucchi A, Allievi N, Harbi A, Pisano M, Montori G, et al. Acute appendicitis: epidemiology, treatment and outcomes—analysis of 16544 consecutive cases. World J Gastrointest Surg. 2016;8:693–699. doi: 10.4240/wjgs.v8.i10.693. PubMed DOI PMC

The EUPEMEN (EUropean PErioperative MEdical Networking) Protocol for Acute Appendicitis: Recommendations for Perioperative Care